(a) Field of the Invention
The present invention relates to a method and apparatus for allocating a resource. More particularly, the present invention relates to a method and apparatus for allocating a resource that can adjust inter-cell interference in a wireless communication system including a plurality of cells.
(b) Description of the Related Art
In order to achieve a high network system capacity, a goal of a 4th generation mobile communication system is to use a frequency reuse 1 method. However, the frequency reuse 1 method becomes a factor that seriously deteriorates performance of a cell boundary user by increasing inter-cell interference (ICI). Furthermore, as the number of base stations per service area increases, a performance deterioration phenomenon of a cell boundary user becomes more serious. Therefore, in order to fully obtain a gain provided in a multi-cell orthogonal frequency-division multiple access (OFDMA) network environment and to provide the same user bodily sensation quality in a global network, effective ICI adjustment is essential.
In order to solve an ICI problem, several dynamic ICI adjustment methods have been researched, and particularly, have been researched based on coupling of power control and user scheduling, but such methods should be operated by a slot-by-slot method and thus generally require high signaling overhead.
Therefore, an ICI adjustment method through a fractional frequency reuse (FFR) technique has been in the spotlight as an actual embodiment method to improve spectral efficiency of a cell boundary user.
Similar to an FFR technique, a soft fractional time reuse (FTR) method using high transmitting power in different resource division between adjacent cells in a time resource area was suggested. FTR provides a high spectral efficiency gain in a low signal to interference-plus-noise ratio (SINR) (e.g., 0 dB or less) area. FFR or FTR methods focus on uniform distribution of traffic or users. Therefore, when inter-cell traffic distribution or user distribution is uniform, there is no problem, but when inter-cell traffic distribution or user distribution is not uniform, a cell having insufficient resources may exist and a cell in which resources remain may exist. Further, when load distributions of the cell center and the cell boundary are not uniform even within one cell, an allocated resource is not used or is insufficient and thus a case in which a service is not appropriately performed may occur. Therefore, in an FFR technique or an FTR technique, a method of optimally operating performance of an entire network according to user distribution and traffic load distribution is requested.